Trying valiantly to laugh along with everyone else, he got up, his feet numb from the weight of the dwarf, as Percy Weasley did his best to disperse the crowd, some of whom were crying with mirth.

There are no more uses of "disperse" in the book.

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By the start of the second round, everyone at our table is dispersing among the crowd.

Colleen Hoover -- Slammed

We engaged in the preliminaries: small talk about Betsy’s family, college, career (all stellar, A-list, awesome), and drinks dispersed for everyone (soda pops and Clamato, which Go and I had come to believe was an affectation of Tanner’s, a quirk he thought would give him character, like my wearing fake glasses in college).